Mass Effect 3 "Squad Leader" Trailer

This video highlights:

An ancient alien race, known only as Reapers, has launched an all-out invasion leaving nothing but a trail of destruction in their wake. Earth has been taken, the galaxy is on the verge of total annihilation, and you are the only one who can stop them. You are Commander Shepard and an elite and battle hardened team is at your side. Each with devasting skills and powerful weapons at their disposal. The War for Earth has begun. Lead your squad and take it back.

An ancient alien race, known only as Reapers, has launched an all-out invasion leaving nothing but a trail of destruction in their wake. Earth has been taken, the galaxy is on the verge of total annihilation, and you are the only one who can stop them. You are Commander Shepard and an elite and battle hardened team is at your side. Each with devasting skills and powerful weapons at their disposal. The War for Earth has begun. Lead your squad and take it back.